Mercedes-Benz bulletin LI20.00-P-076708
What it saysComplaint Check engine lamp activated, coolant warning message, and engine fan running at full speed. NHTSA’s full summary ↓
Mercedes-Benz filed this with NHTSA as a service bulletin dated Sep 9, 2025, received Aug 2, 2023, about the engine — 7 documents under this number. It names 7 model years (2022–2026). A service bulletin is not a safety recall: it is the manufacturer telling its dealers how to diagnose or repair a condition, and whether the work is paid for depends on the warranty in force. Quoting the number at a service desk can save a diagnosis.
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What the bulletin says
Source: NHTSA's summary of the manufacturer's communicationComplaint Check engine lamp activated, coolant warning message, and engine fan running at full speed. Below fault codes stored in N127 PTCU related to LIN network components. U063200, U063287, U02A900, U02A987, U0698E4, U0698E5, U02C800, U02C887, U063B00, U063B87 Cause Under analysis. Remedy Model 254 -Update software of PTCU N127 -Cleared fault codes and check vehicle operation Model 167 Disconnect 12V battery and leave for 20 minutes. Reconnect battery and clear fault codes. Perform 2 test drives, with at least 5 minutes in between with ignition off. If vehicle operates normally, it can be released to the owner. Software solution is in development for PTCU variant 22A. If complaint occurs in vehicle with PTCU version later that 22A please check the following: -Check connections at all LIN bus components connected to N127 PTCU for damage, corrosion, or poor connection -Check wiring between LIN bus components and N127 for damage or chaffing -Inspect intermediate connections between LIN bus components and N127 for damage, corrosion, or poor connection
Documents filed under this number
| Document | Kind | Dated | NHTSA id | At NHTSA |
|---|---|---|---|---|
| LI20.00-P-076708 | Service bulletin | Sep 9, 2025 | 11023049 | PDF, 68 KB |
| LI20.00-P-076708 | Service bulletin | May 15, 2025 | 11018516 | PDF, 68 KB |
| LI20.00-P-076708 | Service bulletin | Jan 31, 2025 | 11013342 | PDF, 68 KB |
| LI20.00-P-076708 | Service bulletin | Jan 17, 2025 | 11012910 | PDF, 68 KB |
| LI20.00-P-076708 | Service bulletin | Dec 6, 2024 | 11011557 | PDF, 37 KB |
| LI20.00-P-076708 | Service bulletin | Apr 15, 2024 | 10253720 | PDF, 35 KB |
| LI20.00-P-076708 | Service bulletin | Jul 24, 2023 | 10240165 | PDF, 38 KB |
The summary is NHTSA’s abstract of the document, as filed under 49 CFR 579.5. One communication is usually filed as several documents — the bulletin, a dealer notice, an owner letter — and the number on any of them finds this page. A PDF link is shown only once NHTSA’s own server has been seen to serve that document; the rest are checked over the following nights. Quote the number at a service desk; it is what the dealer’s system is keyed on.
Model years it names
Source: as the manufacturer filed themA vehicle page’s bulletin list shows the newest few communications filed against that model year; the count there is every one.
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What owners reported
Source: NHTSA complaint databaseOwners of the 7 model years this bulletin names have filed 308 complaints with NHTSA since 2015. 147 of them name Electrical System, Engine — the same broad component group this bulletin is filed under. NHTSA groups complaints coarsely, so that means the same area of the vehicle, not necessarily the same fault.
Brand new car Engine light also went on and off 3 or more times in one day, car had a charging failure wouldn't charge - Sold me an unsafe vehicle to drive - shaking tires, steering wheel, Car also has 13 codes including engine and transmission failure communication codes - multiple attempts to resolve the matter and the service team…
2026 Mercedes-Benz GLC-Class · Engine · filed with NHTSA Jan 6, 2026 · ODI 11709067
On Sunday, XXX at approximately 5:30 PM, I entered the parking lot of a Staples store at , in my 2025 Mercedes Benz AMG GLC 43 SUV. It was daylight and the weather was clear. There was no wind and the temperature was in the low 80s. I drove down a parking aisle and slowed down to make a right turn into an open parking space.
2025 Mercedes-Benz GLC-Class · Electrical System · filed with NHTSA Sep 21, 2026 · ODI 11765946
The contact owns a 2025 Mercedes-Benz GLC 300. The contact stated that while her husband was driving at 5 to 10 MPH attempting to park the vehilce lunged forward traveling 20 feet and crashed into the house. The air bags deployed. No warning lights were illuminated , There was no injuries or fire. A police report was filed.
2025 Mercedes-Benz GLC-Class · Engine · filed with NHTSA Jun 4, 2026 · ODI 11741988
A complaint is one owner’s account, not a defect finding, and a bulletin is not a recall. Nothing here says this bulletin was issued because of these complaints, or that the repair it describes fixed them. Complaint files on this site begin in 2015.
More bulletins about the engine
Source: same model, same component group51 other manufacturer communications filed against these Mercedes-Benz models under the same component group (engine), newest first. The eight newest are listed; the rest are on the Mercedes-Benz list.
| Number | Kind | Dated | NHTSA’s summary |
|---|---|---|---|
| LI18.00-P-073137 | Service bulletin | Sep 26, 2026 | Complaint Sporadic warning message in instrument cluster "Engine oil pressure stop switch off vehicle" (or similar) is shown in red on vehi… |
| LI20.10-P-075374 | Service bulletin | Sep 17, 2026 | Complaint Red coolant warning in instrument cluster. Fault codes U019F00 or U019F87 current/stored in MRG1 control unit. Cause Various cause… |
| LI01.20-P-080884 | Service bulletin | Aug 12, 2026 | Complaint Oil leaks found on M176 or M177 engines diagnosed to be from the cylinder head cover area Cause Unknown (under investigation) Reme… |
| LI07.10-P-080384 | Service bulletin | Aug 7, 2026 | Complaint Customer reports Check Engine Light with possible loss of power concern. The Following DTC's are present • P210185 - The throttle… |
| NCU - 2026010004 | Service campaign | Jul 27, 2026 | • Always use the latest XENTRY Diagnosis software release with all available add-ons. • Make sure to follow the operation steps exactly as d… |
| LI20.10-P-072886 | Service bulletin | Jul 24, 2026 | Complaint Check Engine Light ON with DTC P012800 "The Coolant Temperature is Below the Specified Temperature" active and/or stored in the ME… |
| Emissions - 2024100016 | Emissions | Jul 24, 2026 | Mercedes-Benz AG (“MBAG”), the manufacturer of Mercedes-Benz, has determined that on certain MY 2019-2021 C-Class, G-Class, GLC, GT, S-Class… |
| LI01.30-P-072328 | Service bulletin | Mar 27, 2026 | Complaint -Check engine light illuminated. -Engine runs rough. -Poor shifting or jerking when accelerating. -Fault codes stored related to m… |
Quote the number at the service desk. It is what the dealer’s system is keyed on.
Every manufacturer communication NHTSA holds for Mercedes-Benz, by the number printed on the letter.
Common questions
Source: NHTSA, 49 CFR 579.5Is Mercedes-Benz LI20.00-P-076708 a recall?
No. A service bulletin is a manufacturer communication filed with NHTSA under 49 CFR 579.5; a safety recall carries an NHTSA campaign number (two digits, a letter, six digits) and a federal duty to repair for free. Check the vehicle’s recalls by VIN at nhtsa.gov/recalls, or on its page here.
Is the LI20.00-P-076708 repair free?
Not automatically. A service bulletin describes how to diagnose or repair a condition; who pays depends on the warranty in force, any extension, and the dealer. Quoting the number can save a diagnosis either way. Every Mercedes-Benz warranty extension on file lists the ones Mercedes-Benz has filed.
Which vehicles does LI20.00-P-076708 cover?
The manufacturer filed it against 7 model years: 2026 Mercedes-Benz GLC-Class, 2025 Mercedes-Benz GLC-Class, 2024 Mercedes-Benz GLC-Class, 2023 Mercedes-Benz GLC-Class, 2022 Mercedes-Benz GLC-Class, 2025 Mercedes-Benz GLE-Class and more. Whether one particular vehicle is affected is a matter of its VIN and its build, not its model year alone.